AD 2005-24-03 R1

The FAA is revising an existing airworthiness directive (AD) that applies to certain Boeing Model 737-600, -700, -700C, and -800 series airplanes. That AD currently requires inspecting/measuring the length of the attachment fasteners between the nacelle support fittings and the lower wing skin panels, and related investigative/corrective actions if necessary. That AD resulted from a report from the manufacturer that in production, during the installation of certain attachment fasteners for the nacelle support fittings, only one washer was installed instead of two. This new AD corrects errors found in the existing AD. We are issuing this AD to prevent inadequate fastener clamp-up, which could result in cracking of the fastener holes, cracking along the lower wing skin panels, fuel leaking from the wing fuel tanks onto the engines, and possible fire.

Final rule.

2005-24-03 R1 Boeing: Amendment 39-14955. Docket No. FAA-2006-25000; Directorate Identifier 2006-NM-096-AD. \n\nEffective Date \n\n\t(a) The effective date of this AD is April 12, 2007. \n\nAffected ADs \n\n\t(b) This AD revises AD 2005-24-03. \n\nApplicability \n\n\t(c) This AD applies to Boeing Model 737-600, -700, -700C, and - 800 series airplanes; line numbers 1 through 761 inclusive, except for line numbers 596, 683, 742, 749, 750, 751, 754, 755, 759, and 760; certificated in any category. \n\nUnsafe Condition \n\n\t(d) This AD results from a determination that errors were inadvertently included in the existing AD. We are issuing this AD to prevent inadequate fastener clamp-up, which could result in cracking of the fastener holes, cracking along the lower wing skin panels, fuel leaking from the wing fuel tanks onto the engines, and possible fire. \n\nCompliance \n\n\t(e) You are responsible for having the actions required by this AD performed within the compliance times specified,unless the actions have already been done. \n\nInspection/Measurement and Related Investigative and Corrective Actions \n\n\t(f) At the applicable time specified in paragraph (f)(1) or (f)(2) of this AD: Inspect/measure the length of certain attachment fasteners between the lower wing skin panels and the nacelle support fittings. Do the inspection/measurement, and all applicable related investigative and corrective actions, in accordance with the Accomplishment Instructions of Boeing Service Bulletin 737-57-1275, Revision 1, dated August 18, 2005. After the effective date of this AD only Boeing Service Bulletin 737-57-1275, Revision 3, dated October 17, 2006; shall be used. \n\n\t(1) For Model 737-700 series airplanes modified by Supplemental Type Certificate (STC) ST00830SE as of December 28, 2005 (the effective date of AD 2005-24-03): Accomplish the actions at the later of the times specified in paragraphs (f)(1)(i) and (f)(1)(ii) of this AD. \n\n\t(i) Prior to the accumulation of 25,000 total flight hours or 25,000 total flight cycles, whichever is first. \n\n\t(ii) Within 12 months after December 28, 2005. \n\n\t(2) For all other airplanes: Accomplish the actions at the later of the times specified in paragraphs (f)(2)(i) and (f)(2)(ii) of this AD. \n\n\t(i) Prior to the accumulation of 30,000 total flight hours or 30,000 total flight cycles, whichever is first. \n\n\t(ii) Within 12 months after December 28, 2005. \n\n\t(g) If accomplishing a corrective action as required by paragraph (f) of this AD, and the service bulletin specifies to contact Boeing for repair information: Before further flight, do the repair using a method approved in accordance with paragraph (i) of this AD. \n\nActions Accomplished According to Previous Issue of Service Bulletin \n\n\t(h) Actions accomplished before December 28, 2005, in accordance with Boeing Service Bulletin 737-57-1275, dated September 4, 2003; are considered acceptable for compliance with the corresponding actions specified inthis AD. \n\nAlternative Methods of Compliance (AMOCs) \n\n\t(i)(1) The Manager, Seattle Aircraft Certification Office (ACO), FAA, has the authority to approve AMOCs for this AD, if requested using the procedures found in 14 CFR 39.19. \n\n\t(2) AMOCs approved previously in accordance with AD 2005-24-03, are approved as AMOCs for the corresponding provisions of this AD. \n\n\t(3) Before using any AMOC approved in accordance with 14 CFR 39.19 on any airplane to which the AMOC applies, notify the appropriate principal inspector in the FAA Flight Standards Certificate Holding District Office.\n \n\t(4) An AMOC that provides an acceptable level of safety may be used for any repair required by this AD, if it is approved by an Authorized Representative for the Boeing Commercial Airplanes Delegation Option Authorization Organization who has been authorized by the Manager, Seattle ACO, to make those findings. For a repair method to be approved, the repair must meet the certification basis of the airplane, and the approval must specifically refer to this AD. \n\nMaterial Incorporated by Reference \n\n\t(j) You must use the service information identified in Table 1 of this AD to perform the actions that are required by this AD, unless the AD specifies otherwise. \n\n\tTable 1.--All Material Incorporated by Reference \n\n\nBoeing Service Bulletin\nRevision Level\nDate\n737-57-1275\n1\nAugust 18, 2005\n737-57-1275\n3\nOctober 17, 2006\n\n\n\t(1) The Director of the Federal Register approved the incorporation by reference of Boeing Service Bulletin 737-57-1275, Revision 3, dated October 17, 2006; in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. \n\n\t(2) On December 28, 2005 (70 FR 70713, November 23, 2005), the Director of the Federal Register approved the incorporation by reference of Boeing Service Bulletin 737-57-1275, Revision 1, dated August 18, 2005. \n\n\t(3) Contact Boeing Commercial Airplanes, P.O. Box 3707, Seattle, Washington 98124-2207, for a copy of this service information. You may review copies at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at the National Archives and Records Administration (NARA). For information on the availability of this material at NARA, call 202-741-6030, or go to: http://www.archives.gov/federal-register/cfr/ibr-locations.html.

Examining the Docket \n\n\tYou may examine the AD docket on the Internet at http://dms.dot.gov or in person at the Docket Management Facility office between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The Docket Management Facility office (telephone (800) 647-5227) is located on the plaza level of the Nassif Building at the street address stated in the ADDRESSES section. \n\nDiscussion \n\n\tThe FAA proposed to amend part 39 of the Federal Aviation Regulations (14 CFR part 39) with an airworthiness directive (AD) to revise AD 2005-24-03, amendment 39-14383 (70 FR 70713, November 23, 2005). The existing AD applies to certain Boeing Model 737-600, -700, - 700C, and -800 series airplanes. The proposed AD was published in the Federal Register on June 13, 2006 (71 FR 34026). That action proposed to continue to require inspecting/measuring the length of the attachment fasteners between the nacelle support fittings and the lower wing skin panels, and related investigative/corrective actions if necessary. That action also proposed to correct errors found in the existing AD. \n\nComment \n\n\tWe provided the public the opportunity to participate in the development of this AD. We have considered the comment received. \n\nRequest To Cite Revised Service Information \n\n\tBoeing states that, subsequent to the drafting of the subject AD, Boeing Service Bulletin 737-57-1275, Revision 2, dated July 12, 2006, was issued. Boeing notes that Revision 2 will aid operators in completing the required tasks by more effectively and efficiently performing the inspections, while reducing the likelihood of introducing damage reported during completion of the previous revisions. Boeing recommends that Boeing Service Bulletin 737-57-1275, Revision 3, dated October 17, 2006, be incorporated into the NPRM, which further improves ease in completing the required tasks. (Revision 3 was not yet issued when the comment was submitted, but has since beenissued.) \n\n\tWe agree with this request. We have reviewed Revision 3 of the referenced service bulletin which specifies that no more work is necessary on airplanes changed as shown in the original issue, dated September 4, 2003; Revision 1, dated August 18, 2005; and Revision 2, dated July 12, 2006. (We referred to Revision 1 in the NPRM as the appropriate source of service information for accomplishing the required actions.) We have determined that Revision 3 shows changes of operators in the effectivity and clarifies the oversize limits for replacement fasteners, but does not add any further actions or increase the economic burden on operators. Therefore, we have changed the AD to add Boeing Service Bulletin 737-57-1275, Revision 3, dated October 17, 2006, as the appropriate source of service information for accomplishing the requirements in paragraph (f) of this AD after the effective date of this AD. \n\nConclusion \n\n\tWe have carefully reviewed the available data, including thecomment received, and determined that air safety and the public interest require adopting the AD with the change described previously. We have determined that this change will neither increase the economic burden on any operator nor increase the scope of the AD. \n\nCosts of Compliance \n\n\tThere are about 751 airplanes of the affected design in the worldwide fleet. The following table provides the estimated costs for U.S. operators to comply with this AD. The requirements that were previously required by AD 2005-24-03 are retained in this AD; this AD adds no additional economic burden on U.S. operators. The current costs are repeated for the convenience of affected operators, as follows: \n\nEstimated Costs \n\n\n\nAction\nWork hours\nAverage labor rate per hour\nParts\nCost per airplane\nNumber of U.S.-registered airplanes\nFleet cost\nInspection/\nMeasurement\n12\n$65\nNominal\n$780\n302\n$235,560\n\n\nAuthority for This Rulemaking \n\n\tTitle 49 of the United States Code specifiesthe FAA's authority to issue rules on aviation safety. Subtitle I, Section 106, describes the authority of the FAA Administrator. Subtitle VII, Aviation Programs, describes in more detail the scope of the Agency's authority. \n\n\tWe are issuing this rulemaking under the authority described in Subtitle VII, Part A, Subpart III, Section 44701, "General requirements.'' Under that section, Congress charges the FAA with promoting safe flight of civil aircraft in air commerce by prescribing regulations for practices, methods, and procedures the Administrator finds necessary for safety in air commerce. This regulation is within the scope of that authority because it addresses an unsafe condition that is likely to exist or develop on products identified in this rulemaking action. \n\nRegulatory Findings \n\n\tWe have determined that this AD will not have federalism implications under Executive Order 13132. This AD will not have a substantial direct effect on the States, on the relationship between the national government and the States, or on the distribution of power and responsibilities among the various levels of government. \n\n\tFor the reasons discussed above, I certify that this AD: \n\n\t(1) Is not a "significant regulatory action'' under Executive Order 12866; \n\n\t(2) Is not a "significant rule'' under DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979); and \n\n\t(3) Will not have a significant economic impact, positive or negative, on a substantial number of small entities under the criteria of the Regulatory Flexibility Act. \n\n\tWe prepared a regulatory evaluation of the estimated costs to comply with this AD and placed it in the AD docket. See the ADDRESSES section for a location to examine the regulatory evaluation. \n\nList of Subjects in 14 CFR Part 39 \n\n\tAir transportation, Aircraft, Aviation safety, Incorporation by reference, Safety. \n\nAdoption of the Amendment \n\nAccordingly, under the authority delegated to me by the Administrator, the FAA amends 14 CFR part 39 as follows: \n\nPART 39--AIRWORTHINESS DIRECTIVES \n\n1. The authority citation for part 39 continues to read as follows: \n\n\tAuthority: 49 U.S.C. 106(g), 40113, 44701. \n\nSec. 39.13 (Amended) \n\n2. The Federal Aviation Administration (FAA) amends Sec. 39.13 by removing amendment 39-14383 (70 FR 70713, November 23, 2005) and adding the following new airworthiness directive (AD):